Formwork element of a round formwork

ABSTRACT

A formwork element of a round formwork comprises a form skin ( 1 ), on the backside of which vertically extending profile rails ( 3, 4 ) are disposed, with which horizontally extending curved shaping bars ( 13 ) are detachably connected. The shaping bars ( 13 ) are each formed by at least two, preferably at least four, cast elements ( 14 ), each of which extends over a large portion of the longitudinal extent of the shaping bar ( 13 ), and which are held together by shoes ( 15 ), and, due to a curvature-dependent offset (v) between the cast elements ( 14 ) in the longitudinal direction of the shaping bar ( 13 ) in each instance at least one, preferably at least two, of the cast elements ( 14 ) extend up to the particular front-side end ( 16, 17 ) of the shaping bar ( 13 ).

BACKGROUND OF THE INVENTION

a) Field of the Invention

The invention relates to a formwork element of a round formwork comprising a form skin, on whose backside vertically extending profile rails are disposed, with which horizontal curved shaping bars are detachably connected.

b) Description of Related Prior Art

Formwork elements of this type are known. In order to implement one side of the round formwork (e.g. the outer formwork) from such formwork elements, several formwork elements of this type, to be arranged next to and/or above one another, are connected with one another. The outer and inner formwork can herein be developed analogously. In the region between the vertically extending profile sections, the concrete pressure is borne by the form skin. The shaping bars, also referred to as anchor rails, determine the curved shape of the formwork element. Further, these shaping bars conventionally form the bearing surface and abutment for the anchors of formwork anchored through.

Such formwork elements are reusable. If herein the radius of curvature of the round formwork is to be for example smaller than in the preceding application, the roundness of the dismounted shaping bars is contoured to the required greater curvature by plastic deformation with an appropriate rounding device. Since the shaping bars are disposed radially further inwardly than the form skin, the shaping bars would, after the contouring, project laterally beyond the form skin. The shaping bars are therefore cut correspondingly in order to terminate laterally flush with the form skin. If the formwork element is to be applied in a subsequent use for the production of a round formwork with greater radius of curvature (=smaller curvature), the shaping bars must be replaced since the previous shaping bars are now too short.

Apart from round formworks, in which the shaping bars are deformed by plastic deformation to the desired curvature by means of an appropriate rounding device, mechanical systems are also known, in which the shaping bars comprise articulations, which can be adjusted according to the desired curvature of the formwork element. Of disadvantage herein is the complicated structuring and the elaborate adjustment work of the articulations.

OBJECT AND SUMMARY OF THE INVENTION

One important object of the invention is providing a formwork element of the above described type, which, at simple structuring can be employed for different radii of curvature of the round formwork without cutting the ends of the shaping bars or a replacement of these shaping bars being required.

-   -   This is achieved according to the invention through a formwork         element comprising     -   a form skin,     -   vertically extending profile rails disposed on the backside of         the form skin, horizontally extending curved shaping bars         detachably connected with the profile rails, which [shaping         bars] are each formed by at least two continuous cast elements         each extending over a large portion of the longitudinal extent         of the shaping bars and held together by shoes, in each instance         at least one of the cast elements extending up to the particular         front-side end of the shaping bars due to a curvature-dependent         offset between the cast elements in the longitudinal direction         of the shaping bars.

Consequently, according to the invention one length-adjustable shaping bar is provided. In the case of an inner formwork the shaping bar can thereby be shortened for a greater curvature and, in the case of a lesser curvature, it can be lengthened or, in the case of an outer formwork, it can be lengthened with a greater curvature and shortened with a lesser curvature, such that in each instance it terminates at the edge of the form skin. As a function of the curvature, the cast elements are therein offset relative to one another at variable width. In the case of an inner formwork, the smallest radius curvature for which the formwork element can be employed, is that [radius] at which the cast elements terminate without offset against one another at the side edges of the form skin. In the case of an outer formwork, this is the case at the greatest radius of curvature for which the formwork element can be employed.

The connection of the shaping bars with the vertically extending profile rails preferably takes place via the shoes. For this purpose, these [shoes] can comprise a first clamping part in contact on the profile rail as well as a second clamping part gripping the cast elements on their sides facing away from the form skin, the clamping parts being braced by means of a tightening bolt penetrating bores in the clamping parts and in a web, parallel to the form skin, of a particular profile rail.

In a preferred embodiment of the invention above and beneath a longitudinal opening of the shaping bar at least two cast elements, in contact with one another, are available, of which in each instance at least one extends toward the particular front-side end of the shaping bar. Through the longitudinal openings can penetrate anchor rods for the anchoring through of the formwork.

The cast elements are preferably implemented in the form of plates, thus have the form of a flat rectangle in cross section. Such flat elements can most readily be contoured with the least deformation by means of rollers.

Further advantages and details of the invention will be explained in the following in conjunction with the embodiment example depicted in the drawing. Further objects of the invention are evident therefrom.

BRIEF DESCRIPTION OF THE DRAWING

In the drawing depict:

FIG. 1 a schematic perspective illustration of two formwork elements according to the invention disposed one above the other,

FIG. 2 an enlarged perspective illustration in greater detail of an edge region of the formwork element according to the invention of FIG. 1,

FIG. 3 a rearview of the lower left corner region of the formwork element of FIG. 1,

FIG. 4 a section along line A-A of FIG. 3,

FIGS. 5, 6 and 7 a view (direction of viewing B in FIG. 6), a side view (direction of viewing C in FIG. 5) and a top view (direction of viewing D in FIG. 6) of a clamping part of a shoe for holding together the cast elements,

FIGS. 8 and 9 a side view analogous to FIG. 6 (direction of viewing E in FIG. 9) and a top view analogous to FIG. 7 (direction of viewing F in FIG. 8) of a further embodiment of a clamping part;

FIG. 10 a schematic illustration of a connection unit for connecting the shaping bars of two formwork elements laterally adjoining one another,

FIGS. 11 and 12 a side view analogous to FIG. 6 (direction of viewing G in FIG. 12) and top view analogous to FIG. 7 (direction of viewing H in FIG. 11) of a further embodiment of a clamping part.

DESCRIPTION OF THE PREFERRED EMBODIMENT EXAMPLE

In FIG. 1 two formwork elements according to the invention of an inner formwork of a round formwork are disposed one above the other. The formwork elements of the outer formwork of the round formwork can be implemented in analogous manner. A particular formwork element comprises a form skin 1, which can be comprised for example of wood (for example laminated wood) and is implemented such that it is preferably continuous over the entire width of the formwork element. The form skin 1 can also be implemented to be continuous in height (dimension) or it can be comprised of several adjoining segments. The form skin 1 can, for example, also be formed by a steel plate.

On the backside of the form skin 1, facing away from the form surface 2, several vertically extending profile rails 3, 4 are disposed, e.g. bolted on. Herein two boundary-side profile rails 3 are available, which preferably have a U-form cross section. Each of the open sides of the U-form cross sections of the two boundary-side profile rails 3 faces away from the edge of the formwork elements. The profile rails 3 comprise webs 9, in contact on the backside of the form skin 1 and fastened with the form skin 1, webs 5 extending from webs 9 at the edge and perpendicularly to the form skin 1, and webs 6, extending at the ends of webs 5 remote from the form skin 1 extending from these webs 5 parallel to the form skin 1. The webs 5 perpendicular to the form skin 1 are preferably flush with the front-side ends 7, 8 of the form skin 1.

Between the boundary-side profile rails 3 are disposed at a spacing from one another several vertically extending profile rails 4 on the backside of form skin 1. These profile rails 4 are preferably implemented such that they have a Z-form cross section. They are fastened on form skin 1 with the webs 10 in contact on the backside of form skin 1. From the edge of web 10 projects a web 11 vertically with respect to the form skin, and on the end of web 11, remote from the form skin 1, extends a web 12 extending parallel to the form skin 1. The distances between adjacent profile rails 3, 4 are determined by [the mechanical laws of] statics and can be, for example, in the range between 50 cm and 1.5 m.

With the vertically extending profile rails 3, 4 are detachably connected horizontally extending shaping bars 13. The shaping bars 13 are curved in the horizontal direction, whereby the curvature of the formwork element is determined in the horizontal direction. By varying the curvature of the shaping bars 13 the curvature of the formwork element can be varied.

The more precise implementation of the shaping bars 13 will be explained in the following in conjunction with FIGS. 2 to 9. In the depicted preferred embodiment example, each of the shaping bars 13 comprises four cast elements 14 held together by means of shoes 15. The cast elements 14 are preferably implemented in the form of plates, thus, viewed in cross section, have the form of a flat rectangle. Each of these cast elements 14 extends over a large portion of the longitudinal extent of the shaping bars, but are at least for all curvatures of the shaping bars 13, except for the greatest (in the case of an inner formwork) or the least (in the case of an outer formwork) for the curvature, designated for this formwork element, shorter than the total length of the shaping bar 13. The cast elements 14 are offset relative to one another in the longitudinal direction of the shaping bar 13, and specifically in the depicted arrangement of the two inner cast elements 14 extend up to the front-side end 16, shown in FIG. 2, of the shaping bar 13 and the two other cast elements 14 are spaced apart from this front-side end 16 by the offset v. At the opposite front-side end 17 of the shaping bar 13 the condition is precisely reversed (cf. FIG. 3 with a slightly lesser curvature of the shaping bar). In the mounted position according to FIG. 2, this offset v is relatively small. The offset v increases with decreasing curvature of the shaping bar 13. In FIG. 3 a comparatively somewhat greater offset v is depicted.

If all cast elements 14 extend without mutual offset v at both front-side ends of the shaping bars 13, the greatest (in the case of an inner formwork) or the least (in the case of an outer formwork) curvature is designated for this formwork element.

All of the cast elements 14 have preferably the same length, but they can also be of different lengths.

As stated, the shoes 15 serve for holding together the cast elements 14 and furthermore for preventing them from buckling or being twisted about a horizontal (curved) axis extending in the longitudinal direction of the shaping bar 13. The connection of the shaping bar 13 with the vertically extending profile rails 3, 4, furthermore, preferably takes place via the shoes 15.

In the embodiment example according to FIGS. 2 to 7 each particular shoe 15 is formed by two U-shaped clamping parts 18, 19, which are braced with one another by means of a tightening bolt 20. Each clamping part 18, 19 has a base shank 21 and two side shanks 22. In the side shanks 22 two slots 24 are recessed starting from their free longitudinal edge 23. The slots 24 in the two side shanks 22, viewed in side view (FIG. 6), are congruent. Into the slots 24 are inserted in each instance two adjoining cast elements 14 with their side edges. Into the base shank 21 is introduced a bore 25 at a level between the two slots 24 for the passage of the tightening bolt 20. The bore 25 is here closer to the one side shank 22 than to the other side shank 22.

One of the two clamping parts 18, 19 is in contact on web 6 of the profile rail 3 or on web 12 of profile rail 4. In web 6 or 12 a bore is disposed congruent with bore 25. Into the slot 24 of this clamping part 18 are introduced the one side edges of the cast elements 14. Onto the opposite side edges of cast elements 14 is slipped on the second clamping part 19. In the depicted embodiment example the second clamping part 19 is implemented identically to the clamping part 18, but placed in position rotated by 180 degrees about a horizontal axis and by 180 degrees about a vertical axis relative to the clamping part 18. By means of the tightening bolt 20 penetrating web 6 or 12 and the clamping parts 18, 19, the clamping parts 18, 19 are braced against one another and fastened on the profile rail 3 or 4, respectively. The tightening bolts 20 in the depicted embodiment example are formed by bolts in connection with nuts.

At each point of intersection of the shaping bar 13 and the profile rails 3, 4 is preferably provided a shoe 15 for holding together and aligning the cast elements 14 and for fastening the shaping bar 13 on the profile rails 3, 4. Into the two boundary-side shoes 15 the cast elements 14, spaced apart from the particular front-side end 16, 17, project at a greater or lesser distance and (with smaller curvatures of the formwork element in the case of an inner formwork, or at greater curvatures in the case of an outer formwork) can also terminate before the boundary-side shoe 15. It is in principle also conceivable and possible to provide for this situation a boundary-side shoe with slots 24 implemented in one or both side shanks of the clamping parts 18, 19, the width of which slots corresponds only to the thickness of a single cast element 14.

Between the upper cast elements 14 in contact on one another and the lower cast elements 14 in contact on one another is located a longitudinal opening 26 of the shaping bar 13. Through it can extend an anchor rod 27 of an anchor, such as is shown in FIGS. 3 and 4. On the side edges, facing away from form skn 1, of the cast elements 14 is stayed an anchor plate 28 spanning the cast elements 14. The anchor rod 27 penetrates the anchor plate 28 through a bore in the same and, in the proximity of its ends comprises threads, onto which a nut 29 is screwed. In this way the formworks disposed on both sides of the wall to be erected can be anchored through. The curvature of the formwork (not shown in the Figures) to be disposed on the other side of the wall is the reverse of the formwork elements shown in FIG. 1 (convex instead of concave). As already cited several times, such a convexly curved formwork element can also be implemented in the manner according to the invention, the offset between the cast elements in this case increasing with increasing curvature.

The connection of several formwork elements disposed one above the other can take place in conventional manner, for example by means of tubular pieces 30 disposed at the lower edge of the formwork element, which [tubular pieces 30] are placed onto tubular pieces disposed on the upper end of the lower formwork element and are screwed together with them by means of threaded bolts. For centering the tubular pieces 30 conical recesses 31 and corresponding truncated cone-form extensions (not shown in the Figures) to engage into the conical recesses 31 can be provided.

Formwork elements to be disposed one next to the other can be bolted together via their boundary-side profile rails 3, whose webs 5 are in contact on one another. In the webs 5 bore holes 32 can be disposed for the passage of threaded bolts.

To achieve continuous rigidity of the shaping bars 13 between formwork elements laterally adjoining one another, the shaping bars 13 of the adjacent formwork elements can also be connected with one another via connection units. One possible implementation of such a connection unit is shown schematically in FIG. 10. Two bridge-like brackets 33 are provided. The upper bracket 33 is supported with feet 34 on the upper sides of the shaping bars 13 of the adjacent formwork elements and the lower bracket 33 on the lower sides. In the two edge regions of the bridge webs 35 of brackets 33 transverse webs 36 are welded onto these, which project beyond them on both sides. In the regions in front of and behind the bridge webs 35 the transverse webs 36 include bores, through which extend tightening bolts 37, which brace the two brackets 33 with one another. To the left and the right are provided in each instance two tightening bolts 37 disposed in FIG. 10 one behind the other. Other forms of implementation of connection units for the shaping bars 13 would also be conceivable and possible.

To achieve continuous rigidity between laterally adjoining formwork elements, it would also be conceivable and possible to dispose at levels between the shaping bars 13 preferably horizontally extending connection rails, which extend over both adjoining formwork elements and which are connected with at least one of the profile rails 3, 4 of a particular formwork element. They are here preferably in any case connected with the two boundary-side profile rails 3, adjacent to one another, of the two formwork elements. The connection rails could herein be implemented analogously to the shaping bars 13 and their connections with the profile rails 3 and/or 4 could also analogously take place by means of shoes 15.

If the curvature of the formwork element is to be changed, the tightening bolts 20 are loosened, whereupon the cast elements 14 can be dismantled. The cast elements 14 are plastically deformed to the desired curvature with a contouring device (by means of appropriate rollers). The shaping bars 13 are subsequently reassembled, the cast elements 14 being correspondingly offset, and the tightening bolts 20 tightened. In the proximity of the two front-side ends 16, 17 of the shaping bars 13 at least the particular cast elements 14, extending up to these front-side ends 16, 17, should extend through the boundary-side shoes 15. The shaping bars 13 can thereby be connected with the boundary-side profile rails 3.

FIGS. 8 and 9 show a modified embodiment example of a clamping part 18 of a shoe. The clamping part 18 comprises a base shank 38 and edge shanks 39 disposed at both ends of the same. In the central region of the base shank 38 side shanks 40 are disposed at its two side edges, which shanks are overlapping in the side view according to FIG. 8. The slots 24 for the insertion of the cast elements 14 are here formed between the edge shanks 39 and the side shanks 40.

A further modified embodiment example of a clamping part 18 of a shoe is depicted in FIGS. 11 and 12. The clamping part is implemented in the form of an H to increase its rigidity, with side shanks 22 and a connection shank 41, comprising bore 25. From the longitudinal edges 23 of the side shanks 22 on the one side of the clamping part, again, slots 24 extend for receiving the cast elements 14.

At the front-side ends 7, 8 the form skin is preferably provided with an edging protection 42. (FIG. 4). This can be formed for example by a metal web welded onto the profile rail 3, which metal web overlaps at the front-side the form skin 1 preferably comprised of wood, and between this web and the form skin 1 a silicon joint can be implemented.

Various modifications of the depicted embodiment example of the invention are conceivable and possible without going beyond the scope of the invention. For example, more or fewer cast elements 14 can be provided. It would also be conceivable and possible, for example, that the shaping bar 13 is formed by two cast elements 14 implemented such that they are U-shaped in cross section, which are correspondingly offset in the longitudinal direction of the shaping bar 13. In order to make possible an interspace for the passage of anchor rods 27, it could also be provided here to place the two U-shaped cast elements with the free ends of their side shanks in contact with one another, the free ends of the side shanks being locally provided with indentations for the formation of the longitudinal opening.

It would also be conceivable and possible to implement the boundary-side profile rails 3, instead of in the depicted U-shaped implementation, in the same manner as the profile rails 4, thus as Z-profiles. The web extending spaced apart from the form skin 1 and parallel to the form skin 1 could in this case be disposed for example pointing away in each instance from the side edge of the formwork element. The web vertical with respect to the form skin 1, would, in case of the Z-form implementation of the profile rails 4, be spaced apart from the front-side end 7, 8 of the formwork element. The shaping bars 13 can extend beyond this web to the particular front-side end 16, 17 and preferably, again, terminate flush with it. To connect two laterally adjoining formwork elements, again, connection rails could be provided disposed at levels between the shaping bars 13 and connected with the profile rails 3 and/or 4. In addition, at levels between the shaping bars 13 or the connection rails, respectively, plate-form elements could be bolted onto the webs, spaced apart from the form skin 1 and extending parallel to it, of the adjacent profile rails 4 in order to be able to absorb shearing forces acting in the vertical direction.

U-form or Z-form implementations, other than those depicted and described, of the profile rails 3, 4 would also be conceivable and possible, for example such having the form of an H.

As is evident based on the above description, the scope of the invention is not limited to the depicted embodiment examples, but rather should be determined with reference to the attached claims together with their full range of possible equivalents.

While the above description and the drawing represent the invention, it is obvious to a person skilled in the art that various changes can therein be carried out without leaving the true spirit and scope of the invention.

Legend to the Reference Numbers

-   1 Form skin -   2 Form surface -   3 Profile rail -   4 Profile rail -   5 Web -   6 Web -   7 Front-side end -   8 Front-side end -   9 Web -   10 Web -   11 Web -   12 Web -   13 Shaping bar -   14 Continuous cast element -   15 Shoe -   16 Front-side end -   17 Front-side end -   18 Clamping part -   19 Clamping part -   20 Tightening bolt -   21 Base shank -   22 Side shank -   23 Longitudinal edge -   24 Slot -   25 Bore -   26 Longitudinal opening -   27 Anchor rod -   28 Anchor plate -   29 Nut -   30 Pipe piece -   31 Conical recess -   32 Bore hole -   33 Bracket -   34 Foot -   35 Bridge web -   36 Transverse web -   37 Tightening bolt -   38 Base shank -   39 Edge Shank -   40 Side shank -   41 Connection shank -   42 Edging protection 

1. Formwork element of a round formwork comprising a form skin (1), vertically extending profile rails (3, 4) disposed on the backside of the form skin (1), horizontally extending curved shaping bars (13), detachably connected with the profile rails (3, 4), each formed of at least two cast elements (14), each of which extends over a large portion of the longitudinal extent of the shaping bar (13) and which are held together by shoes (15), and, due to the curvature-dependent offset (v) between the cast elements (14) in the longitudinal direction of the shaping bar (13), in each instance at least one of the cast elements (14) extends up to the particular front-side end (16, 17) of the shaping bar (13).
 2. Formwork element as claimed in claim 1, in which each of the shaping bars (13) is formed by at least four cast elements (14).
 3. Formwork element as claimed in claim 1, in which, due to the offset (v) between the cast elements (14), in each instance at least two of the cast elements (14) extend up to the particular front-side end (16, 17) of the shaping bar (13).
 4. Formwork element as claimed in claim 1, in which the connection of the shaping bars (13) with the vertically extending profile rails (3, 4) takes place via the shoes (15).
 5. Formwork element as claimed in claim 4, in which tightening bolts (20) are provided, which penetrate webs (6, 12) of the vertically extending profile rails (3, 4) and the shoes (15).
 6. Formwork element as claimed in claim 5, in which screw connections are implemented by the tightening bolts (20).
 7. Formwork element as claimed in claim 1, in which one longitudinal opening (26) of the shaping bar (13) in each instance is delimited upwardly and downwardly by at least two cast elements (14) in contact on one another, of which at least one extends to the particular front-side end (16, 17) of the shaping bar (13).
 8. Formwork element as claimed in claim 1, in which the cast elements (14) are implemented in the form of plates.
 9. Formwork element as claimed in claim 1, in which the cast elements (14) have identical lengths.
 10. Formwork element as claimed in claim 1, in which each of the shoes (15) comprises two clamping parts (18, 19) and the two clamping parts (18, 19) are braceable against one another with the cast elements (14) by means of a tightening bolt (20).
 11. Formwork element as claimed in claim 10, in which the clamping parts (18, 19) have slots (24) for receiving the segments of the cast elements (14) adjoining the side edges of the cast elements (14).
 12. Formwork element as claimed in claim 11, in which the clamping parts (18, 19) have base shanks (21, 38), disposed parallel to the form skin (1), in which is disposed a bore (25) for the passage of a tightening bolt (20).
 13. Formwork element as claimed in claim 12, in which the bore (25) is laterally offset in the longitudinal direction of the shaping bar (13) with respect to the center of the base shank (21, 38).
 14. Formwork element as claimed in claim 1, in which the connection units (33, 34, 35, 36, 37) are provided for the connection of the shaping bars (13) of two laterally adjoining formwork elements.
 15. Formwork element as claimed in claim 14, in which the connection unit (33, 34, 35, 36, 37) comprises brackets (33) braced from above and from below against the shaping bar by means of tightening bolts (37).
 16. Formwork element as claimed in claim 1, in which the formwork element comprises at both side edges a vertically extending profile rail (3), which has a web (5) terminating flush with the side edge of the form skin (1).
 17. Formwork element as claimed in claim 16, in which several vertically extending profile rails (4) are provided between the vertically extending boundary-side profile rails (3).
 18. Formwork element as claimed in claim 1, in which for each formwork element at least two horizontally extending shaping bars (13) are provided spaced apart from one another in the vertical direction.
 19. Formwork element as claimed in claim 1, in which in the case of an inner formwork at all curvatures, except for the greatest curvature designated for this formwork element or, in the case of an outer formwork at all curvatures except for the smallest curvature designated for this formwork element, at least one of the cast elements (14) is spaced apart from the front-side end (16, 17) of the shaping bar (13).
 20. Formwork element as claimed in claim 19, in which in the case of an outer formwork at all curvatures, except the smallest curvature designated for this formwork element, at least two of the cast elements (14) are spaced apart from the front-side end (16, 17) of the shaping bar (13).
 21. Formwork element as claimed in claim 1, in which for the connection of laterally adjoining formwork elements connection rails disposed at levels between the shaping bars (13) are provided, which extend at least over boundary-side regions of the adjoining formwork elements and are connected with at least one profile rail (3, 4) of a particular formwork element.
 22. Formwork element as claimed in claim 21, in which the connection rails extend horizontally.
 23. Formwork element as claimed in claim 21, in which the connection rails are formed analogously to the shaping bars (13) by at least two cast elements (14) each extending over a large portion of the longitudinal extent of the connection rail and disposed by means of shoes (15) on the profile rails (3, 4) of the formwork elements.
 24. Formwork element as claimed in claim 23, in which the connection rails are formed of at least four cast elements (14) each extending over a large portion of the longitudinal extent of the connection rails. 